OBJECTIVES: Our overall objective is to undertake an investigation of selected species of organisms in the order Mycorplasmatales. The organisms will be studied in terms of three-dimensional morphology, ultrastructure, and replication. Organism/cell interactions will be investigated by use of tissue culture cell lines and techniques of morphometry. The relationships between cell and organism will be assessed by light microscopy, electron microscopy and scanning electron microscopy. Aerosols of Mycoplasma pulmonis and for comparison a bovine species will be studied in terms of viability at different relative humidities and for distribution during delivery into an exposure chamber. The effect of an air pollutant-ozone on mycoplasmata will be studied and rabbits will be exposed to ozone before and after exposure to aerosol. BIBLIOGRAPHIC REFERENCES: Boatman, E.S. and Kenny, G.: Morphometry, Morphology and Ultrastructure of HeLa cell cultures infected with Mycoplasma sp. Bact. Proc. 1976. Boatman, E.S., Cartwright, F., and Kenny, G.: Morphology, Morphometry, and electron microscopy of HeLa cell cultures infected with bovine Mycoplasma. Cell and Tissue Research. 1976.